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Genomic Diversity of Campylobacter lari Group Isolates from Europe and Australia in a One Health Context. Appl Environ Microbiol 2022; 88:e0136822. [PMID: 36354326 PMCID: PMC9746300 DOI: 10.1128/aem.01368-22] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Members of the Campylobacter lari group are causative agents of human gastroenteritis and are frequently found in shellfish, marine waters, shorebirds, and marine mammals. Within a One Health context, we used comparative genomics to characterize isolates from a diverse range of sources and geographical locations within Europe and Australia and assess possible transmission of food, animal, and environmental isolates to the human host. A total of 158 C. lari isolates from Australia, Denmark, France, and Germany, which included 82 isolates from human stool and blood, 12 from food, 14 from domestic animal, 19 from waterbirds, and 31 from the environment were analyzed. Genome-wide analysis of the genetic diversity, virulence, and antimicrobial resistance (AMR) traits was carried-out. Most of the isolates belonged to C. lari subsp. lari (Cll; 98, 62.0%), while C. lari subsp. concheus and C. lari urease-positive thermotolerant Campylobacter (UPTC) were represented by 12 (7.6%) and 15 (9.5%) isolates, respectively. Furthermore, 33 (20.9%) isolates were not assigned a subspecies and were thus attributed to distant Campylobacter spp. clades. Whole-genome sequence-derived multilocus sequence typing (MLST) and core-genome MLST (cgMLST) analyses revealed a high genetic diversity with 97 sequence types (STs), including 60 novel STs and 14 cgMLST clusters (≤10 allele differences), respectively. The most prevalent STs were ST-21, ST-70, ST-24, and ST-58 (accounting for 13.3%, 4.4%, 3.8%, and 3.2% of isolates, respectively). A high prevalence of the 125 examined virulence-related loci (from 76.8 to 98.4% per isolate) was observed, especially in Cll isolates, suggesting a probable human pathogenicity of these strains. IMPORTANCE Currently, relatedness between bacterial isolates impacting human health is easily monitored by molecular typing methods. These approaches rely on discrete loci or whole-genome sequence (WGS) analyses. Campylobacter lari is an emergent human pathogen isolated from diverse ecological niches, including fecal material from humans and animals, aquatic environments, and seafood. The presence of C. lari in such diverse sources underlines the importance of adopting an integrated One Health approach in studying C. lari population structure for conducting epidemiological risk assessment. This retrospective study presents a comparative genomics analysis of C. lari isolates retrieved from two different continents (Europe and Australia) and from different sources (human, domestic animals, waterbirds, food, and environment). It was designed to improve knowledge regarding C. lari ecology and pathogenicity, important for developing effective surveillance and disease prevention strategies.
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Identification of domestic reservoirs and common exposures in an emerging lineage of Shiga toxin-producing Escherichia coli O157:H7 in England: a genomic epidemiological analysis. THE LANCET MICROBE 2022; 3:e606-e615. [DOI: 10.1016/s2666-5247(22)00089-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 03/24/2022] [Accepted: 03/29/2022] [Indexed: 01/01/2023] Open
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Sim EM, Kim R, Gall M, Arnott A, Howard P, Valcanis M, Howden BP, Sintchenko V. Added Value of Genomic Surveillance of Virulence Factors in Shiga Toxin-Producing Escherichia coli in New South Wales, Australia. Front Microbiol 2022; 12:713724. [PMID: 35002991 PMCID: PMC8733641 DOI: 10.3389/fmicb.2021.713724] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 11/22/2021] [Indexed: 11/25/2022] Open
Abstract
The disease caused by Shiga toxin-producing Escherichia coli (STEC) remains a significant public health challenge globally, but the incidence of human STEC infections in Australia remains relatively low. This study examined the virulence characteristics and diversity of STEC isolates in the state of New South Wales between December 2017 and May 2020. Utilisation of both whole and core genome multi-locus sequence typing (MLST) allowed for the inference of genomic diversity and detection of isolates that were likely to be epidemiologically linked. The most common STEC serotype and stx subtype detected in this study were O157:H7 and stx1a, respectively. A genomic scan of other virulence factors present in STEC suggested interplay between iron uptake system and virulence factors that mediate either iron release or countermeasures against host defence that could result in a reduction of stx1a expression. This reduced expression of the dominant stx genotype could contribute to the reduced incidence of STEC-related illness in Australia. Genomic surveillance of STEC becomes an important part of public health response and ongoing interrogation of virulence factors in STEC offers additional insights for the public health risk assessment.
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Affiliation(s)
- Eby M Sim
- Enteric Reference Laboratory and Microbial Genomics Laboratory, Centre for Infectious Diseases and Microbiology Laboratory Services, NSW Health Pathology, Institute of Clinical Pathology and Medical Research, Westmead, NSW, Australia
| | - Ryan Kim
- Enteric Reference Laboratory and Microbial Genomics Laboratory, Centre for Infectious Diseases and Microbiology Laboratory Services, NSW Health Pathology, Institute of Clinical Pathology and Medical Research, Westmead, NSW, Australia
| | - Mailie Gall
- Enteric Reference Laboratory and Microbial Genomics Laboratory, Centre for Infectious Diseases and Microbiology Laboratory Services, NSW Health Pathology, Institute of Clinical Pathology and Medical Research, Westmead, NSW, Australia
| | - Alicia Arnott
- Enteric Reference Laboratory and Microbial Genomics Laboratory, Centre for Infectious Diseases and Microbiology Laboratory Services, NSW Health Pathology, Institute of Clinical Pathology and Medical Research, Westmead, NSW, Australia
| | - Peter Howard
- Enteric Reference Laboratory and Microbial Genomics Laboratory, Centre for Infectious Diseases and Microbiology Laboratory Services, NSW Health Pathology, Institute of Clinical Pathology and Medical Research, Westmead, NSW, Australia
| | - Mary Valcanis
- Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, VIC, Australia
| | - Benjamin P Howden
- Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, VIC, Australia
| | - Vitali Sintchenko
- Enteric Reference Laboratory and Microbial Genomics Laboratory, Centre for Infectious Diseases and Microbiology Laboratory Services, NSW Health Pathology, Institute of Clinical Pathology and Medical Research, Westmead, NSW, Australia.,Marie Bashir Institute for Infectious Diseases and Biosecurity, The University of Sydney, Sydney, NSW, Australia.,Centre for Infectious Diseases and Microbiology-Public Health, Westmead Hospital, Westmead, NSW, Australia
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Carroll CJ, Hocking DM, Azzopardi KI, Praszkier J, Bennett-Wood V, Almeida K, Ingle DJ, Baines SL, Tauschek M, Robins-Browne RM. Re-evaluation of a Neonatal Mouse Model of Infection With Enterotoxigenic Escherichia coli. Front Microbiol 2021; 12:651488. [PMID: 33815340 PMCID: PMC8013722 DOI: 10.3389/fmicb.2021.651488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Accepted: 02/17/2021] [Indexed: 12/03/2022] Open
Abstract
Enterotoxigenic E. coli (ETEC) is a common cause of diarrhea in children in low- and middle-income countries, and in travelers to these countries. ETEC is also an important cause of morbidity and premature mortality in piglets, calves, goat kids and lambs. The major virulence determinants of ETEC are enterotoxins and colonization factors, which enable the pathogen to colonize the small intestine and deliver enterotoxins, such as the heat-stable enterotoxins, STp and STh, to epithelial cells. Because most ETEC strains are host-specific, there are few convenient animal models to investigate the pathogenesis of ETEC infections or to evaluate specific anti-ETEC interventions, such as drugs and vaccines. An exception is ETEC strains bearing F41 pili, which mediate intestinal colonization of various young animals, including neonatal mice, to cause disease and in some cases death. In this study, we used the archetypal F41-producing bovine ETEC strain, B41 (O101:NM; K99, F41, STp) to validate and further explore the contribution of F41 and STp to bacterial virulence. By using targeted gene deletion and trans-complementation studies, augmented by whole genome sequencing, and in vitro and animal studies of virulence, we established that F41 mediates colonization of the mouse intestine and is essential for bacterial virulence. In addition, we showed for the first time that STp is as important as F41 for virulence. Together, these findings validate the use of neonatal mice to study the pathogenesis of F41-bearing ETEC and to investigate possible specific anti-ETEC interventions including vaccines that target heat-stable enterotoxins.
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Affiliation(s)
- Carla J Carroll
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia
| | - Dianna M Hocking
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia
| | - Kristy I Azzopardi
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia.,Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, VIC, Australia
| | - Judyta Praszkier
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia
| | - Vicki Bennett-Wood
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia
| | - Kaylani Almeida
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia
| | - Danielle J Ingle
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia
| | - Sarah L Baines
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia
| | - Marija Tauschek
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia
| | - Roy M Robins-Browne
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, VIC, Australia.,Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, VIC, Australia
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Baines SL, da Silva AG, Carter GP, Jennison A, Rathnayake I, Graham RM, Sintchenko V, Wang Q, Rockett RJ, Timms VJ, Martinez E, Ballard S, Tomita T, Isles N, Horan KA, Pitchers W, Stinear TP, Williamson DA, Howden BP, Seemann T. Complete microbial genomes for public health in Australia and the Southwest Pacific. Microb Genom 2020; 6:mgen000471. [PMID: 33180013 PMCID: PMC8116684 DOI: 10.1099/mgen.0.000471] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 10/21/2020] [Indexed: 12/13/2022] Open
Abstract
Complete genomes of microbial pathogens are essential for the phylogenomic analyses that increasingly underpin core public health laboratory activities. Here, we announce a BioProject (PRJNA556438) dedicated to sharing complete genomes chosen to represent a range of pathogenic bacteria with regional importance to Australia and the Southwest Pacific; enriching the catalogue of globally available complete genomes for public health while providing valuable strains to regional public health microbiology laboratories. In this first step, we present 26 complete high-quality bacterial genomes. Additionally, we describe here a framework for reconstructing complete microbial genomes and highlight some of the challenges and considerations for accurate and reproducible genome reconstruction.
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Affiliation(s)
- Sarah L. Baines
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, Victoria 3001, Australia
| | - Anders Gonçalves da Silva
- Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Victoria 3001, Australia
| | - Glen P. Carter
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, Victoria 3001, Australia
| | - Amy Jennison
- Public Health Microbiology, Queensland Reference Centre for Microbial and Public Health Genomics, Forensic and Scientific Services, Queensland Department of Health, Archerfield, Queensland 4108, Australia
| | - Irani Rathnayake
- Public Health Microbiology, Queensland Reference Centre for Microbial and Public Health Genomics, Forensic and Scientific Services, Queensland Department of Health, Archerfield, Queensland 4108, Australia
| | - Rikki M. Graham
- Public Health Microbiology, Queensland Reference Centre for Microbial and Public Health Genomics, Forensic and Scientific Services, Queensland Department of Health, Archerfield, Queensland 4108, Australia
| | - Vitali Sintchenko
- Centre for Infectious Diseases and Microbiology – Public Health, Westmead Hospital and NSW Health Pathology, Sydney, New South Wales 2145, Australia
- Marie Bashir Institute for Infectious Diseases and Biosecurity, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Qinning Wang
- Centre for Infectious Diseases and Microbiology – Public Health, Westmead Hospital and NSW Health Pathology, Sydney, New South Wales 2145, Australia
| | - Rebecca J. Rockett
- Centre for Infectious Diseases and Microbiology – Public Health, Westmead Hospital and NSW Health Pathology, Sydney, New South Wales 2145, Australia
- Marie Bashir Institute for Infectious Diseases and Biosecurity, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Verlaine J. Timms
- Centre for Infectious Diseases and Microbiology – Public Health, Westmead Hospital and NSW Health Pathology, Sydney, New South Wales 2145, Australia
- Marie Bashir Institute for Infectious Diseases and Biosecurity, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Elena Martinez
- Centre for Infectious Diseases and Microbiology – Public Health, Westmead Hospital and NSW Health Pathology, Sydney, New South Wales 2145, Australia
| | - Susan Ballard
- Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Victoria 3001, Australia
| | - Takehiro Tomita
- Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Victoria 3001, Australia
| | - Nicole Isles
- Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Victoria 3001, Australia
| | - Kristy A. Horan
- Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Victoria 3001, Australia
| | - William Pitchers
- Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Victoria 3001, Australia
| | - Timothy P. Stinear
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, Victoria 3001, Australia
| | - Deborah A. Williamson
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, Victoria 3001, Australia
- Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Victoria 3001, Australia
| | - Benjamin P. Howden
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, Victoria 3001, Australia
- Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Victoria 3001, Australia
| | - Torsten Seemann
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, Victoria 3001, Australia
- Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Victoria 3001, Australia
| | - Communicable Diseases Genomics Network (CDGN)
- Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Parkville, Victoria 3001, Australia
- Microbiological Diagnostic Unit Public Health Laboratory, Department of Microbiology and Immunology, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Victoria 3001, Australia
- Public Health Microbiology, Queensland Reference Centre for Microbial and Public Health Genomics, Forensic and Scientific Services, Queensland Department of Health, Archerfield, Queensland 4108, Australia
- Centre for Infectious Diseases and Microbiology – Public Health, Westmead Hospital and NSW Health Pathology, Sydney, New South Wales 2145, Australia
- Marie Bashir Institute for Infectious Diseases and Biosecurity, The University of Sydney, Sydney, New South Wales 2006, Australia
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Abstract
Enterohemorrhagic E. coli is a significant human pathogen that can cause severe disease due to the release of Shiga toxins. The toxins are encoded within lysogenic bacteriophage and controlled by antitermination of the phage late promoter, PR′. This promoter is always active, but terminated immediately downstream during lysogeny. A byproduct of antitermination regulation is transcription of a short RNA that is thought to be nonfunctional. Here we demonstrate that in Shiga toxin-encoding phages, this short RNA is a Hfq-binding regulatory small RNA. The small RNA represses toxin production threefold under lysogenic conditions and promotes high cell density growth. Lysogenic bacteriophages are highly abundant and our results suggest that antiterminated phage promoters may be a rich source of regulatory RNAs. Enterohemorrhagic Escherichia coli is a significant human pathogen that causes disease ranging from hemorrhagic colitis to hemolytic uremic syndrome. The latter can lead to potentially fatal renal failure and is caused by the release of Shiga toxins that are encoded within lambdoid bacteriophages. The toxins are encoded within the late transcript of the phage and are regulated by antitermination of the PR′ late promoter during lytic induction of the phage. During lysogeny, the late transcript is prematurely terminated at tR′ immediately downstream of PR′, generating a short RNA that is a byproduct of antitermination regulation. We demonstrate that this short transcript binds the small RNA chaperone Hfq, and is processed into a stable 74-nt regulatory small RNA that we have termed StxS. StxS represses expression of Shiga toxin 1 under lysogenic conditions through direct interactions with the stx1AB transcript. StxS acts in trans to activate expression of the general stress response sigma factor, RpoS, through direct interactions with an activating seed sequence within the 5′ UTR. Activation of RpoS promotes high cell density growth under nutrient-limiting conditions. Many phages utilize antitermination to regulate the lytic/lysogenic switch and our results demonstrate that short RNAs generated as a byproduct of this regulation can acquire regulatory small RNA functions that modulate host fitness.
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Pintara A, Jennison A, Rathnayake IU, Mellor G, Huygens F. Core and Accessory Genome Comparison of Australian and International Strains of O157 Shiga Toxin-Producing Escherichia coli. Front Microbiol 2020; 11:566415. [PMID: 33013798 PMCID: PMC7498637 DOI: 10.3389/fmicb.2020.566415] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 08/17/2020] [Indexed: 12/20/2022] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) is a foodborne pathogen, and serotype O157:H7 is typically associated with severe disease. Australian STEC epidemiology differs from many other countries, as severe outbreaks and HUS cases appear to be more often associated with non-O157 serogroups. It is not known why Australian strains of O157 STEC might differ in virulence to international strains. Here we investigate the reduced virulence of Australian strains. Multiple genetic analyses were performed, including SNP-typing, to compare the core genomes of the Australian to the international isolates, and accessory genome analysis to determine any significant differences in gene presence/absence that could be associated with their phenotypic differences in virulence. The most distinct difference between the isolates was the absence of the stx2a gene in all Australian isolates, with few other notable differences observed in the core and accessory genomes of the O157 STEC isolates analyzed in this study. The presence of stx1a in most Australian isolates was another notable observation. Acquisition of stx2a seems to coincide with the emergence of highly pathogenic STEC. Due to the lack of other notable genotypic differences observed between Australian and international isolates characterized as highly pathogenic, this may be further evidence that the absence of stx2a in Australian O157 STEC could be a significant characteristic defining its mild virulence. Further work investigating the driving force(s) behind Stx prophage loss and acquisition is needed to determine if this potential exists in Australian O157 isolates.
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Affiliation(s)
- Alexander Pintara
- Centre for Immunology and Infection Control, Queensland University of Technology, Herston, QLD, Australia
- School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, QLD, Australia
| | - Amy Jennison
- Public Health Microbiology, Forensic and Scientific Services, Queensland Health, Brisbane, QLD, Australia
| | - Irani U. Rathnayake
- Public Health Microbiology, Forensic and Scientific Services, Queensland Health, Brisbane, QLD, Australia
| | - Glen Mellor
- CSIRO Animal, Food and Health Sciences, Archerfield, QLD, Australia
| | - Flavia Huygens
- Centre for Immunology and Infection Control, Queensland University of Technology, Herston, QLD, Australia
- School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, QLD, Australia
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McAuliffe GN, Tse F, Qiao H, Moore S, Bissessor L, Thompson B, McLaughlin V, Upton A, Taylor SL. Isolate independent molecular typing improves the yield of O typing of infections due to Shiga toxin producing Escherichia coli. Pathology 2020; 52:460-465. [PMID: 32317174 DOI: 10.1016/j.pathol.2020.02.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Revised: 01/05/2020] [Accepted: 02/21/2020] [Indexed: 11/19/2022]
Abstract
Molecular screening has increased detection of Shiga-toxin producing Escherichia coli (STEC). However, it is difficult to isolate the organism for epidemiological typing. We applied a molecular method for direct detection of nine O types from 110 stx positive faeces samples and compared the results with conventional isolate based methods. Using conventional methods 55/110 (50%) samples were O typed. Using the molecular method, 72/110 (65%) were O typed, including 23/38 (61%) culture negative samples. Combining both techniques typed 88/110 (80%) of samples. Molecular typing increased detection of O128 (2-25%, p<0.001), O26 (11-16%) O45 (0-6%) and O103 (1-6%) infections. Molecular typing of STEC direct from faecal samples improved O type yield; risk of bias in epidemiological and surveillance activities may be reduced by inclusion of culture independent typing methods.
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Affiliation(s)
| | - Fifi Tse
- Department of Microbiology, Middlemore Hospital, Auckland, New Zealand
| | - Helen Qiao
- Department of Microbiology, Middlemore Hospital, Auckland, New Zealand
| | - Sharon Moore
- Department of Microbiology, Labtests, Auckland, New Zealand
| | | | - Bryn Thompson
- Auckland Regional Public Health Service, Auckland, New Zealand
| | | | - Arlo Upton
- Department of Microbiology, Labtests, Auckland, New Zealand
| | - Susan L Taylor
- Department of Microbiology, Middlemore Hospital, Auckland, New Zealand
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